"MMBasic is a free and open BASIC interpreter for 32 bit microcontrollers."

On the other hand:

"The files may not be distributed or made available to others without specific written permission.
Object files (ie, .o, .exe, .hex files) generated using one or more of the source files (modified or not) are for personal use only and may not be distributed without written permission.
The files are provided without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose."

The RPF will not do this because this software is not open source or public license. There is nothing preventing an individual from downloading and compiling the source code to an executable format as long at that individual abides by and follows the agreed upon terms.

“In order for the firmware to work pigpio software version 64 must be installed …” — ah, it is, via the pigpio package

“The firmware requires privileged access to the Pi hardware and so must be run using the sudo command sudo ./mmbasic” — eww, really? That's a bit 2014.

“The Pi-cromite firmware sits in a tight loop polling for input and so will use 100% of one CPU. It is running at priority zero most of the time so the operating system is able to time-slice processor access. During time-sensitive I/O operations the priority will be raised and other processes locked out.” — aaaaiiiiiiiiiiiiiiiieeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee!!!!!!!!!!!!!!!!!!!!!!111!!!!!!!!!!!! (FX; runs away screaming, optional Goons-style splosh indicating having run off the end of Canada)

I'm sure it's a cool program, but it's not a “firmware”: it's a program. Unless you run it under one of the bare-metal OSs, I kind of expect to be able to do other things, like copy and paste from the terminal your command is running in. Also, the closed-source thing is a big nah.

‘Remember the Golden Rule of Selling: “Do not resort to violence.”’ — McGlashan.